Hypertrichosis

Key Points
Characterized by excessive or abnormal hair growth on the body
It can develop all over the body or be occur in isolated parts of the body
Hypertrichosis can occur at birth or later in life.
Hirsutism differs in that it refers to increased hair growth in women in a pattern more typically seen in men (such as the beard or mustache)

Congenital Hypertrichosis is a very rare disorder (there are only around 50 cases on record, dating back hundreds of years). The congenital variety is caused by a rare flaw in pregnancy; a fine hair covers the fetus, which usually falls off around the eighth month. However, in these cases, that hair doesn’t disappear, it continues to grow after birth. There are two types of hypertrichosis: generalized (all over the body) or localized (which occurs only on certain sections of the body). Congenital forms of hypertrichosis are genetic and apparent at birth.

Acquired forms of hypertrichosis are more common, occur later in life, and often result from side effects of drugs, cancer, or eating disorders. In cases of acquired hypertrichosis, the hair may contain pigment or it may not.

Differential Diagnosis (Other conditions with similar appearance)
Hirsutism

Diagnosis
Key Points
Characterized by excessive hair growth
The hair may be longer than expected, and can consist of any hair type (fine, normal, coarse)
Generalized hypertrichosis is characterized by hair all over the body
Localized hypertrichosis is characterized by excessive hair which is restricted to certain areas

Hypertrichosis is caused by a genetic mutation, although it can be caused by a spontaneous genetic mutation later in life. Interestingly, in congenital cases, females pass the mutation along to 50 percent of her offspring, while male carriers pass it along to only their female offspring.

The acquired variety of hypertrichosis, which can come late in life, may accompany cancer; it may result from a metabolic disorder; or it can result from the side effects of drugs, such as Minoxidil. Eating disorders such as anerexia can also cause acquired hypertrichosis.

Treatment
There is no cure for the congenital (genetic) hypertrichosis.
Management of the disease is possible by shaving, epilation (plucking, Waxing, electrology) or possibly permanent Hair removal through the use of chemicals targeting hair growth areas or laser surgery.
* Treatment for the acquired form of hypertrichosis is based on attempting to address the underlying cause.

The rare form of congenital hypertrichosis has no cure, unfortunately. However, it can be managed, to some degree, by shaving, waxing, plucking, etc., though such methods may only last from between a few hours to a few weeks. There are chemical procedures, though laser Hair removal has proven most effective.

As for acquired hypertrichosis, that is treated by addressing the underlying problem, be it a metabolic disorder, cancer, an eating disorder, or the side effects of drugs (discontinuing the drug, for instance, will cause the hypertrichosis to reverse).